Electronic devices, such as computers, or personal data assistants (PDA's), often have a relatively thin display panel for viewing a visual display produced by the electronic device. In some of these electronic devices, the display panel is to some extent flexible, and can, for example, be spread or folded, e.g. over a surface that may be rigid, but may also be bendable, pliable or supple. The display panel may be rollable, in that in can be bent in successive layers around an axis and pulled out or unfurled for use, for example from a housing, in particular a tubular housing.
Electronic devices with displays may be wearable. A flexible image display apparatus may be attached to clothes, for example, as disclosed in patent publication no. US20020144442 A1, published Oct. 10, 2002, in patent publication no. US 20040187184 A1, published Sep. 30, 2004 and in patent publication no. US 20020019296 A1, published Feb. 14, 2002, which are incorporated herein by reference.
Flexible displays may be in a tablet-like form, including a central processing unit (CPU), drive circuitry for an active matrix of the display, memory storage unit and other components of the display. Tablet-like display panels sometimes include traditional control devices such as buttons, joysticks, thumbwheels, and touch pads, for controlling the image displayed on the display panel, inputting data, and moving cursors that are provided as part of the visual display. This approach is, for example, disclosed in United States Patent Application Publication US 2002/0070910 A1, to Fujieda, et al., PCT Publication WO/01/50232, to Zhang, et al, and PCT Publication WO 98/03962, of Johnson, et al., which are incorporated herein by reference.
Rollable as well as flexible displays are becoming commercially available. Very thin (e.g. 0.1 mm) flexible displays have been developed that can be rolled up to a radius of 1 cm. Rollable or flexible displays may have electrophoretic frontplanes of polymer material, joined to an active matrix backplane of material which is also flexible or rollable. The term “bendable” is used herein to mean a display or screen, connector or other display component that is flexible in any direction, including a direction of rotation, e.g. a display screen or ribbon cable or other connector that can be folded back on itself.
The display device may, however, also advantageously be a liquid crystal display device, electrochromic display device, reflective display device including, for example, an interferometric modulator and luminescent display device, rather than an electrophoretic display. The display devices may be passive or be an active matrix display. Examples of such active matrix display devices are TFT-LCDs or AM-LCDs, (O) LED devices, which are used in laptop computers and in organizers, and are also finding increasingly wider application in GSM telephones.
Prior, copending application 60/636,022 filed Dec. 14, 2004, which is incorporated by reference herein, discloses a “modular display super stick”. A housing includes a rollable display panel which provides a large display in the unrolled position, and can be rolled in the housing when not use, thus providing a small form factor. The housing may also have drive electronics for the display, including, for example, a controller or processor and power source such as batteries.